Distribution and control arrangement for two-stroke engines



Nov. 24, 1925. 1,562,735

L. BONGIOVANNI DISTRIBUTIOQ AND CONTROL RRANGEMENT FOR TWO-STROKE ENGINES Filed Oct. 51, 1924 Zpvenfaf:

lwaazjan o Va Patented Nov. 24, 1925.

UNITED STATES LUCA BONGIOVANNI, F POI-LING, ITALY.

DISTRIBUTION AND CONTROL ARRANGEMENT FOR TW'O-STROKE ENGINES.

Application filed Uctober 31, 19%.

To all 207mm 232? may come/'22 Be it known that I, Luca Boxoroxxmxr, subject of the Kingdom oi Italy, residing at 'lorino, Italy, have invented certain new and useful Improvements in Distribution and Control Arrangements for Two-Stroke Engines, of which the following is a specilication.

The present invention relates to improvements in distribution and control arrange ments for two-stroke engines, in which the explosive mixture is first of all compressed within the crank case to suitable pressures, which will vary according to the altitude at which the engine is running and to atmospheric conditions, by means of control devices and according to the different characteristics which it is desired to give to the cycle at different atmospheric pressures and temperatures.

These arrangements are characterized by the fact that the communication between the crank case which forms the compression chamber and the explosion chamber, is obtained by means of a tube which is rigid with the piston, by way of ports which are opened and closed when the piston reaches the correct positions. They are moreover characterized by the fact that suitable means are provided for changing the moment of opening and closing of the ports as also the values of the pressures in the two chambers at corresponding moments.

In the accompanying drawings, Figures 1 and 2 are views in vertical section of two constructions according to the present invention, which only differ from one another in the arrangement of the communication ports between the crank case and the explosion chamber.

In Fig. is shown a modified arrangement adapted either for the admission or the exhaust.

In both constructions illustrated, the piston l is provided with a tube 2 open at the top which moves within a throat 3 which forms a continuation of the cylinder. The admission of the explosive mixture takes place by way of the ports 5 when they are uncovered by the piston but it may be effect ed by ports 5 provided with flap valves 5". The exhaust takes place by way of ports 6 similar to the ports 5 and similarly disposed. Large plugs 7 and 8 which may be variously arranged and shaped, allow of varying the Serial No. 747,037.

volume of the explosion and compression chambers and consequently the value of the pressures produced in them corresponding to ditlerent positions of the piston.

In the coi'istruction illustrated in Fig. 1 gas tightness between the tube 2 and the explosion chamber t is assured by means of a ring or rings 9 arranged in the throat 8, and capable of being displaced parallel to the axis, so that it is possible to alt-er the moment at which the transfer ports 10 of the tube 2 come into communication with the chamber at and permit admission into the chamber oi the compressed mixture, in order to com plete the compression and produce the explosion.

In the construction illustrated in Fig. 2, gas tightness is assured by means of a ring or rings 9 rigidly connected with the tube 2 and capable of being displaced in the throat 3, in the lower edge of which throat are arranged transfer ports 10. In this case regulation may be effected by axial displacement of the throat or by a sleeve carrying the ports and disposed within the throat 3.

The operation of these means of distribution requires that the passage of the mixture through the admission and exhaust ports 5, 6, should be absolutely sure and complete. The ports must, however, be numerous and they must have a very considerable aggregate opening and must open into a roomy and suitably disposed collector. To this end annular collectors 11, 11 may be employed of a section which increases as it approaches the pipes 12, 12. Tlese collectors embrace the whole periphery of the cylinder, and enclose the ports which are distributed all around the periphery of the cylinder. If desired, the construction just described can be substituted by the arrange ment illustrated in Fig. 3, in which the cylinder is cut in two, the two parts being slightly spaced and connected by the collector 11".

I claim:

1. In an internal combustion engine, the combination of a cylinder having inlet and exhaust ports and also having an upstanding axial throat at its upper end which is closed at its top; a hollow piston in said cylinder having an open-topped upstanding tubular projection on its upper face which extends into said throat and is spaced circumferentially from the same, the throat and tube constituting companion elements one of which is formed adjacent an end thereof with a set of transfer ports to enable the passage of the explosive mixture from the space between such elements into the explosion chamber of the cylinder; and a gastight ring disposed in said space and encircling said tube.

2. In an internal combustion engine, the combination of a cylinder having inlet and exhaust ports and also having anupst-anding axial throat at its upper end which is closed at its top; a hollow piston in said cylinder having an open-topped upstanding tubular projection on its upper face which extends into said throat and is spaced circumterentially from the same, said throat being formed adjacent its lower end with a series of transfer ports to enable the passage of explosive mixture from the space between the throat and tube into the explosion chamber of the cylinder; and a gas-tight ring in said space encircling the upper end of said tube and rigidly secured thereto.

3. An explosion engine, according to claim 2, in which the upstanding throat is structurally separate from and movable relatively to the engine cylinder to adjust the position of the transfer ports.

In testimony whereof I affix my signature.

LUCA BONGIOVANNI. 

